Generation and destruction of intrinsic and impurity defects in CsJ-Na

Relaxation of absorption bands of Vsub(K)- and Na0-centres created in CsJ-Na crystal by electron pulse (10 ns, 250 keV, 1000 A) is investigated. Data on absorption experiments has been compared with luminescence kinetics (lambda=420 nm) for clarifyng mechanism of recombination process resulting in appearance of scintillation. Measurements have been conducted in the 100-250 K temperature range. Absorption drops in band maxima of Vsub(K) and Na0-centres as well as luminescence damping after the end of accelerator pulse comply with kinetics of the second order. Activation energy for the processes of absorption drop and luminescence damping is equal to 0.19+-0.02 eV that coincides with the value of activation energy or reorientation motion of Vsub(K)-centres in CsJ. Activation energy for luminescence growth is equal to 0.13 eV. Based on the obtained experimental data it is concluded that index of recombination process resulting in CsJ-Na scintillations is of hole type